Two-dimensional problem of determining two unknowns in a viscoelasticity equation for a weakly horizontally inhomogeneous medium

Two-dimensional problem of determining two unknowns in a viscoelasticity equation for a weakly horizontally inhomogeneous medium

(Russian, English abstract)

Totieva Z. D.
Siberian Electronic Mathematical Reports, 22, 2, pp. 1094-1122 (2025)

УДК 517.958 
DOI: 10.33048/semi.2025.22.068  
MSC 35L20, 35R30, 35Q99


Abstract:

A two-dimensional inverse problem of determination of wave propagation velocity and kernel in a viscoelasticity equation for a weakly horizontally inhomogeneous medium is presented. The direct
initial-boundary value problem for the displacement function contains zero initial data and the Neumann condition of a special form. The source of wave propagation is the Dirac delta function. For inverse problem statement the displacement Fourier transform  is given at the border of the half-space. It is assumed that the wave propagation velocity, kernel and displacement decom-poses into an asymptotic series. In this paper, we construct a method for determining unknowns functions with an accuracy of $O(\varepsilon^2)$, where $\varepsilon$ is a small parameter. The theorems of global unique solvability and stability are proved.

Keywords: linear viscoelasticity, inverse problem, delta function, Fourier
transform, kernel, coefficient, stability.